The Arla dairy in Kruså, Denmark, is one of the country’s largest white cheese production sites—and a frontrunner in digital process optimization. As part of its sustainability efforts and desire to reduce production losses, the dairy has implemented continuous monitoring of its membrane filtration systems using optical sensors manufactured by Satron Instruments and supplied by Tech Instrumentation.
Real-Time Purity Monitoring in UF and RO Systems
“The Arla dairy in Kruså has invested in sensors connected to their ultrafiltration (UF) and REVERSE OSMOSE (RO) systems. The sensors measure the purity of the permeate (which passes through the filter – filtrate) and thus the effectiveness of the membrane filtration.”
These real-time sensors immediately detect fat, protein, or lactose residues in the permeate. This enables the process control system to alarm operators of any performance drop, such as from worn membranes or faulty seals.
“If there are residues of fat, protein or lactose in the permeate, then the sensor provides immediately an alarm in the process control system. Then the operator can step in and correct the error so that the membrane filtration is always as efficient as possible.”
Sustainability and Process Efficiency Go Hand in Hand
“It protects against product loss and has also environmental benefits, which together help to ensure more sustainable production.”
The optical sensor, Satron VOD, monitors light absorption at different wavelengths depending on the application. It can be used, for example, to identify milk residues in water, helping to avoid unnecessary loss of valuable components.
“This is detected by the sensor immediately and gives an alarm to the process operator who can get the O-ring changed, and then the membrane filtration system can get back to full production again.”
“Without the sensor, the valuable substances would – here fat and protein – run into the permeate and are lost, thereby the yield of membrane filtration is significantly reduced.”
Ensuring Maximum Yield of All Milk Components
“The reason is that the permeate from the UF plant contains valuable lactose that is not filtered out in the UF system. The lactose is concentrated by membrane filtration in the dairy’s reverse osmosis plant… This means that all the constituents of the milk are utilized, which is included to ensure optimal utilization of milk and a more sustainable operation of the dairy.”
By continuously monitoring the condition of the membranes, the dairy can better schedule maintenance and avoid system degradation.
“With the information from the sensors, as well as analyzes of the permeate, we hope to be able to change in the future the membranes in a timely manner as preventive maintenance, whereby it is ensured that the operation of the UF plants is as optimal as possible,” says Tobias Krause